Fire door



Aug. 14, 1951 N. MICHELMAN FIRE DOOR 3 Sheets-Sheet 1 Filed Dec. 2, 1949 INVENTOR.

TTOENEY Aug. 14, 1951 N.'MICHELMAN 2,564,208

FIRE DOOR Filed Dec. 2, 1949 v 3 Sheets-Sheet 2 IN V EN TOR.

N. MICHELMAN FIRE DOOR Aug. 14, 1951 3 Sheetis-Sheet 5 Filed Dec. 2, 1949 INVENTOR.

Patented Aug. 14, 1951 UNITED STATES PATENT OFFICE FIRE DOOR Nathan.- Miehelm n, Brookl n, N Y- ApplicationDecember 2, 1949, Serial No. 130,705

4 Claims- 1 This invention relates to automatic fire closures, such as fire doors, fire shutters, and the like, and more particularly to a fire doorof the rolling typeparticularly adapted for use in piers, wharves and other industrial structures.

Such doors are flexible and arranged to be wound around a shaft or drum at the head or lintel' of a doorway, and generally comprise a series of metallic strips, slats or panels which are interconnected for relative hinged movement, the opposite ends of such strips being .guided within vertical tracks at each side of the-doorway opening. The door is actuable foropening and closing in response to operation or the door rolling mechanism by hand through themedium of achain and gearing, and is actuable automatically for closing by mechanism operable in response to a rise in-temperature indicative of a fire.

In all of these types of doors, and particularly where they are raised manually, counter+balancing mechanism is considered essentialto reduce the force necessary to raise or roll-up the door and to govern the speed of descent to avoid injury to any one caught in the doorway opening during a door lowering movement.

The present invention is directed to animprovedoperating mechanism for-such doors,-ineluding an improved counter-balancing means and improved automatic release features. To this end, the door winding drum or sleeve is rotatably mounted on a fixed'sha-faand: one or more torsion springs are connected between the sleeve and the shaft for charging, or winding, during rollin up of the door. A second shaft has a friction bearing in the inner endof the f ed shaft. and its outer end earriesan axially movable first 0114190 member- 9231 series is connected between the tWO sheits insueh-me nor that it is charged or wonndou ins lowering of the door, and thus actsas a :connter alence durin roll n up of thedoo ,A second clutch member is .rotateblymounted on the r a able sha t, adjac nt the irst cl ch member, d i conn c d to e doo -win drum. "This second clutch member is normally meshed with gearing included in a chain operated, manual door roll up arrangement. The first clutch member carries teeth coopera'ble with a pair of opposing dogs on ari-ng surrounding the same, said-ring being pivotally mounted so that under gravity -it is concentric to the axis thereof, said ring upon alternate :coaction of its .dogs with the teeth of said clutch being osciliatable in an arc eccentric to the eon of said first clutch member. Normally, the automatic door release maintains this ring in eccentric, em.- bracing as to one dog, but otherwise spaced relative to the first clutch member.

The automatic door release includes a pair of leverspivotally mounted on the housing for the door operating mechanism, these levers being ad..- iustably interconnected for movement as a unit. One lever carries a weight on its free end, and both levers are held in an elevated position by the usual fusible link chain which, upon a D138:- determined temperature rise in the vicinity of the door, breaks to drop the levers. .Of the two levers, one is secured to the shaft of a clutch engaging fork mechanism to engage the clutch members when released by the fusible "link chain. The other lever is secured to a sleeve freely mounted on such shaft and carrying an eccentrically mounted roller normally holding the es.- cillati'ng ring in eccentric relation to the first clutch member. When the levers drop, the roller is released to allow oscillation of the ring now maintained under gravity which, in an oscillating or rockin manner described hereinafter, controls the rate of descent of the door. In such descent, the torsion spring or springs engaged with the fixed mounting shaft and the door wind.- ing drum'bias the drum to unroll the door.

One of the members of the gear train between the hand operating chain and the second clutch member is rotatably mounted on a swing-able arm. This arm is normally held in a position engaging the gear member with associated gear i-ng in the gear train by a cam roller eccentrically mounted on a weighted lever. The latter is held in an upper position by the fusible link chain.

When the us ble ink chain breaks. the wei hted eve dro allo ing th to fal t d op th gear member out of the ge train, the weihted leyer ac i g fu he t nost yely move the a dow wardly. T is dis onnects t ese ond clutch mem and th con cte um, f m the h nd -ro'l-ling door operating mechanism.

These, andotherobjects, advantages and novel features of the invention will be apparent from the following description and the accompanying meanin s. in the draw n s;

Fig. 1 is a front elevation view of a fire door embodying the invention;

Fig. 2 is a vertical sectional view of the door on the line 2--2 of Fig. l

Fig. 3 is a horizontal sectional View on the line 3-3 of Fig. 1;

Fig. 4 is an enlarged, partial front elevation view of part of the control mechanism;

Fig. 5 is a side elevation view of the control mechanism shown in Fig. 4;

Fig. 6 is a rear elevation view of the control mechanism;

Fig. 7 is a horizontal sectional view through the control mechanism;

Fig. 8 is an enlarged horizontal sectional view of the mechanism at the right of Fig. '7; and

Fig. 9 is an enlarged horizontal sectional view of the mechanism at the right of Fig. 7 with the clutch members in engagement.

Referring to Figs. 1, 2 and 3, door It] may comprise a plurality of hingedly interconnected strips or slats ll slidable in vertical tracks i2 and arranged to be wound on a drum mounted within a transversely curved longitudinal draft guard [3 supported as on a lintel [4. The automatic control is mounted at the right, as viewed in Fig. 1, being encased in a housing 58. Control 28 includes interconnected arms 28 and supported by a fusible link chain ll trained over a pulley l8 and including extensions such as 2! extending through guard I3. Arm 25 is weighted as at 22. The door is manually operated by a chain 23 extending from a gear housing 24 and cooperable with a chain lock 26 which may be mounted on a track [2 or on a wall 27.

Referring to Figs. 4 through 8, a normally fixed shaft 38 is mounted in a bearing 28 in an end wall 3| of guard 13 and has keyed to its outer end a drum 32 having apertures 33 adapted to receive a bolt or pin 34 mounted in a bracket 38 on wall 3|. Normally, drum 32 and attached shaft 38 are held stationary, but pin 34 may be disengaged to provide for turning of shaft 38 to effect a pre-set initial charging of torsion springs 35, 31. Shaft extends freely through a circular bracket 38 mounted on a bearing 89 on shaft 38 and secured to door winding drum [5.

Next to bracket 38 is a conical clutch 48, secured to drum [5 and having shaft 88 extend freely therethrough. Spring 31 is engaged with clutch 48 and with a second conical clutch 4| secured to shaft 38. Beyond clutch 4| is a third conical clutch 42 secured to shaft 38 and engaged with one end of spring 35. The other end of spring is engaged with clutch 48, and springs 35 and 31 are charged during unwinding of door ill or drum 15 so as to assist the re-winding of the door, thus reducing the amount of effort required to raise the door.

Beyond clutch 42, shaft 38 has secured thereto a circular spacer plate 43. The innermost end of shaft 38 has a socket receiving an Oilite friction bearing 44 in which is engaged the innermost end of a rotatable shaft 58. A torsion spring 45 is engaged with a conical clutch 48 on shaft 38 and a conical clutch 41 on shaft 58, spring 45 being charged during winding of door 18 so as to bias shaft 58 to rotate in a door unwinding direction. Through clutch mechanism to be described, shaft 50 is connected to drum [5 during automatic release of door l0 so that spring 45 assists the action of gravity in unwinding the door. Shaft 58 has a frictional fit in bearing 44 such that it is normally held against turning relative 4 to shaft 3|] but can be relatively rotated by the application of a torque.

The outer end of shaft 58 has secured thereto a first clutch member 55 carrying a clutching ring 58 on its inner surface and having teeth 51 (Fig. 5) on its periphery. Member 55 has a channelled hub 58 which is engaged by rollers 59 on arms 6| secured to a shaft 62 mounted in brackets 63 on a wall 54 of guard [3. One end of shaft 62 is secured to the inner end of lever 25, which is connected by adjustable means 48 to lever 28.

Just beyond clutch 41, a drum 49 secured to drum I5 is keyed to a sleeve 5| rotatable on shaft 58 and supported in a bearing 52 in wall 84. The outer end of sleeve 5i has keyed thereto a second clutch member 55 having a clutch ring 68 on its outer face and gear teeth 67 on its periphery.

A sleeve 53 is freely mounted on shaft 52 inwardly of arm 25 and forming part of arm 20. Radial arms 54 on sleeve 53 support a roller 68. Roller 68 engages an arm TI on a ring l8 which spacedly surrounds first clutch member 55 and has a pair of teeth or dogs 12, I3 cooperable with teeth 57 of member 55. Ring 18 is oscillatably mounted on a pin l4 engaged in a bracket 16 mounted on wall 84, said ring under such mounting being maintained by gravity in position concentric to the first clutch member 55. Normally, roller 68 engaging arm H retains ring 18 eccentric with member 55, and with dog 12 in tooth holding position.

Manual door-winding chain 23 is trained over a sprocket ll rotatable in housing 24 and carrying a pinion l8 meshing with a gear 8| also rotatably supported on housing 24. Gear Si is fixed to a pinion 82 meshing with a pinion 83 rotatable on a shaft 84 mounted on wall 64. An arm 85 oscillatable on shaft 84 carries, intermediate its ends, a pinion 88 meshing with pinion 84 and the teeth 81 of member 65, when arm 85 is in its upper position (Figs. 5 and 6). Arm 85 is laterally confined by a bracket 81 on wall 84 and is held in the upper position by a roller 88 on an arm 89 of a lever 98 oscillatable on a pin 9| on wall 84. The outer end of lever 98 is secured to fusible link extension 2 I.

Normally, the parts occupy the position shown in Figs. 4 through 8, which represent the door It! in the rolled up position, with fusible link chain ll holding levers 28, 25 and 88 in the elevated position. Clutch members 55 and 65 are disengaged and chain 23 is engaged with lock 26 holding the door in the upper position. In this position, springs 35 and 31 have been substantially discharged by relative rotation between drum l5 and shaft 30. As stated, these springs may, if desired, be given an initial charge by rotation of drum 82 before pin 34 is set in place.

Assumin that a fire occurs and the resulting temperature rise effects a breaking of chain l1, levers 28 and 25 drop. Thelever Zll swings arm 54 counter-clockwise to disengage roller 68 from arm ii on ring 10, permitting it to be oscillated toward concentric relation to the axis of clutch member 55. Lever 25 rocks shaft 62 counterclockwise (Fig. 4) causing arms 6| and their rollers 59 to move clutch member 55 to engage clutch member 65. At the same time, lever 98 drops, releasing arm 85 to follow. As roller 88 moves counter-clockwise, it engages hook 92 on the other end of arm 85 accelerating and making positive the downward movement of arm 85. Such movement disengages pinion 86 from pinion 84 and teeth 67 of clutch member 85. The latter 5. is therefore freed from chain 23 and may rotate with clutch member 55.

The weight of the door starts drum l turning in a direction to lower the door. This action is assisted by the turning force exerted on shaft 20 by spring 45 which was charged during the winding up of the door, shaft 20 bein connected to drum I 5 through clutch 55--i5. As the door lowers, clutch member 55 is turned and its teeth alternately trike dogs 12 and 13 on ring Hi, which has by gravity moved toward a concentric position relative to members 55 due to release of arm H by roller 68. Each time a tooth 5! strikes dog 73, ring is rocked or oscillated and thereby displaced in an eccentric are relative to the axis of clutch member 55 to engage dog 72 with an opposite tooth 51 and vice-versa. This oscillation of ring 10, alternately engaging dogs 12 .and T3 with teeth 51 controls therate. of downward movement of the door. During-suchdownward movement, turning of shaft 5c relative to shaft 30, in friction bearing 44, charges springs 35 and 31.

To re-set the door, lever; 90 is swung clockwise so that roller 88 engages arm 35 to raise the latter to engage pinion 86 with pinion 83 and member 65. As the gear train between sprocket 11 and member 65 is now complete, movement of chain 23 will rotate member 65 in a door winding direction. Member 55 is still engaged with member 65 so that shaft 50 being turned charges spring 45. When the door has been fully raised, levers and 25 are lifted and the break in chain I 1 restored. This lifting of the two levers disengages members 55 and t5 and engages roller 68 with arm 1! to restore ring 70 to the concentric position of Fig. 5. The door is now again in the operative position.

While a pecific embodiment of the invention has been shown and described in detail to illustrate the application of the invention principles, it should be understood that the invention may be otherwise embodied without departing from such principles.

What is claimed is:

1. Operating mechanism for a rolling fire shutter comprising, in combination, a fixed shaft, a rotatable shaft concentrically aligned with said fixed shaft and having an end supported in an end of said fixed shaft, a drum rotatably mounted on said aligned shafts and arranged to have the shutter wound thereon, first torsion spring means secured between said fixed shaft and said rotatable shaft and charged, during winding of the door on said drum, to bias said rotatable shaft in a door unwindin direction, second torsion spring mean secured between said fixed shaft and said drum and charged, during unwinding of the door, to counter-balance the door weight during winding of the door on said drum, a first clutch member secured to said rotatable shaft, a second clutch member secured to said drum, manually operable door winding means, gearing interconnecting said door winding means and said second clutch member, said gearing including an element mounted intermediate the ends of an arm pivotally mounted at one end for swinging movement in a vertical plane, gravity biased means normally maintaining said arm in a position holding said element in operative relation in the gearing, a clutch operating member biased to a position engaging said clutch members, and fire detector means restraining said gravity biased means in the arm maintaining position and said operating member in the clutch disengaging position whereby, when said detector means operates upon occurrenceof a fire, said gravity biased means is released to release said arm to disengage said element to uncouple said second clutch member from said windin means,- and to release said operating member to engage said clutch members to couple said drum and said rotatable shaft during unwinding of the door under the influence of gravity and said first tors'ion spring means, said gravity biased means including an abutment engageable with said swinging arm to positively force the latter downward to disconnect said gearing.

2. Mechanism as claimed in claim 1, including.

means activated by said fire detector means and cooperable with said first clutch member to regulate the rate of unwinding of the door.

3. In operating mechanism for. a rolling fire shutter of the type comprising a fixed shaft, a rotatable shaft concentrically aligned with said fixed shaft and having an end supported in. an end of saidfixed shaft, a drum rotatably' mounted on said aligned shafts and arranged to have the shutter wound thereon, first torsion sprin means secured between said" fixed shaft and. said rotatable shaft and charged, during winding of the door on said drum, to bias said rotatable shaft in a door unwinding direction, second torsion spring mean secured between said fixed shaft and said drum and charged, during unwinding of the door, to counter-balance the door weight during winding of the door on said drum, a first clutch member secured to said rotatable shaft, a second clutch member secured to said drum, a gravity influenced operating member biased to engage said clutch members, and fusible fire detector means restraining said operating member to a clutch disengaging position; door speed controlling mechanism comprising, in combination, ratchet teeth on the periphery of said first clutch member, a ring spacedly surrounding said first clutch member and havin a pair of circumferentially spaced dogs alternately cooperable with said ratchet teeth, said ring being oscillatably mounted relative to said first clutch member and gravity influenced to move to a position eccentric thereto to alternately engage a dog with said teeth, said operating member including holding means normally maintaining said rin concentric with said first clutch member and releasing said ring upon movement of said operating member to clutch engaging position.

4. Operating mechanism for a rolling fire shutter comprising, in combination, a fixed shaft, a rotatable shaft aligned with said fixed shaft and having its inner end frictionally engaged in the inner end of said fixed shaft, a drum arranged to have the shutter wound thereon, a bearing ro-= tatably supporting one end of said drum on the outer portion of said fixed shaft, a sleeve rotatably supporting the other end of said drum on the outer portion of said rotatable shaft, first torsion spring means secured between said fixed shaft and said rotatable shaft and charged, during winding of the door on said drum, to bias said rotatable shaft in a door unwinding direction, second torsion pring means secured between said fixed shaft and said drum and charged, during unwinding of the door, to counter-balance the door weight during winding of the door on said drum, a first clutch member secured to said rotatable shaft, said first clutch member having ratchet teeth on it periphery, a second clutch member secured to said sleeve and having gear teeth on its periphery, manually operable door winding means, gearing interconnecting said door winding means, and said second clutch member, said gearing including an element mounted on a swingin arm, a first weighted lever carrying a roller cam engaging said arm, in the upper position of said lever, to hold said arm in a position holding said element in operative relation in the gearing, a ring spacedly surrounding said first clutch member and having a pair of circumferentially spaced dogs alternately cooperable with said ratchet teeth, said ring having a radial abutment normally biasing the ring to swing to a position eccentric to said first clutch member to en age one of said dogs with said ratchet teeth, a rock shaft carrying a fork engageable with said first clutch member, a second weighted lever secured to said rock shaft and, in its upper position, positionin said fork to disengage said clutch members, a sleeve carrying a cam roller engageable with said abutment and mounted on said rock shaft, a third lever secured to said sleeve, said roller, in the upper position of said third lever, engaging said abutment to hold said ring concentric with said first clutch member, means adjustably interconnecting said second and third levers, and a fusible link chain attached to all three levers and holding the same in the upper position, said chain breaking upon occurrence of a predetermined temperature rise, to release the levers, said first lever effecting disengagement of said gearing element to uncouple said winding means, said second lever effecting engagement of said clutch means, and said third lever effecting release of said ring so that said ring is oscillated by said dogs strikin said ratchet teeth alternately to regulate the rate of unwinding of the door, said first lever including an abutment engageable with said swinging arm to positively force the latter to a gear disconnectin position.

NATHAN MICHELMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,530,652 Cornell Mar. 24, 1925 1,709,305 Brunst Apr. 16, 1929 1,718,752 McCloud June 25, 1929 1,795,390 Graystone Mar. 10, 1931 

